Polyacrylate acrylic rubber

Mechanical Properties of Thermoplastic Elastomers Based on Acrylate Rubber-Fluorocarbon Rubber-Polyacrylate Monomer... 

The acrylic plastics use the term acryl such as polymethyl methacrylate (PMMA), polyacrylic acid, polymethacrytic acid, poly-R acrylate, poly-R methacrylate, polymethylacrylate, polyethylmethacrylate, and cyanoacrylate plastics. PMMA is the major and most important homopolymer in the series of acrylics with a sufficient high glass transition temperature to form useful products. Repeat units of the other types are used. Ethylacrylate repeat units form the major component in acrylate rubbers. PMMAs have high optical clarity, excellent weatherability, very broad color range, and hardest surface of any untreated thermoplastic. Chemical, thermal and impact properties are good to fair. Acrylics will fail in a brittle manner, independent of the temperature. They will suffer crazing when loaded at stress about halfway to the failure level. This effect is enhanced by the presence of solvents. 

In the poly(ethyl acrylate)rubbers described above spirobenzopyran and aromatic azo chromophores were incorporated in the cross-links between the polyacrylic chains. In contrast, Matejika and al. studied cross-linked systems with azo side groups they considered especially the relative importance of the thermal effects occurring during photomechanical conversion. Most interesting are their results on copolymers ccmtaining low concentrations of chromophore (for which heat effects are less important), namely copolymers of )8-hydroxyethyl methacrylate (0.99) and azonaphthol methacrylate (XII) (0.01) swollen in water... 

Currently, a PA6-acrylic rubber-based TPV blend is commercialized by Zeon Chemical tmder the trade name of Zeotherm . Zeotherm is composed predominantly of a heat- and oil-resistant polyacrylate (ACM) elastomer, which has been dynamically vulcanized and well dispersed in a polyamide (PA6) thermoplastic matrix. Based on the patent literature (Aonuma et al. 1991),... 

The above selective cross-linking of acrylate rubbers in a polyamide thermoplastic matrix leads to a PA-acrylate rubber-blend TPV with the melt-processing advantages of the PA and the high-performance properties of a thermoset acrylate rubber. The PA matrix provides the high heat resistance and solvent resistance while the cross-linked polyacrylate provides the rubber elasticity coupled with its own excellent weatherabdity and oil resistance properties to the TPV. 

Acrylic rubber can be emulsion- and suspension-polymerized from acrylic esters such as ethyl, butyl, and/or methoxyethyl acetate to produce polymers of ethyl acetate and copolymers of ethyl, butyl, and methoxyl acetate. Polyacrylate rubber, such as Acron from Cancarb Ltd., Alberta, Canada, possesses heat resistance and oil resistance between nitrile and silicone rubbers. Acrylic rubbers retain properties in the presence of hot oils and other automotive fluids, and resist softening or cracking when exposed to air up to 392°F (200°C). The copolymers retain flexibility down to -40°F (-40°C). Automotive seals and gaskets comprise a major market. These properties and inherent ozone resistance are largely due to the polymer s saturated backbone (see Table 3.13). 

As with other rubbers, acrylate rubbers must be vulcanized before they exhibit useful technological properties. It is possible to cross-link straight polyacrylates by various means. For example, treatment with a peroxide leads to abstraction of tertiary hydrogen and subsequent cross-linking, e.g. ... 

The important characteristics of acrylate rubbers are good oil resistance and good heat resistance carbon black reinforced materials age very well in air up to about 200 C. It is these properties which account for the major use of acrylate rubbers, i.e., in oil seals for automobiles. Polyacrylates are fairly readily hydrolyzed to poly(sodium acrylate) by heating with aqueous sodium hydroxide for a few hours. 

Acrylic rubber Polyacrylate rubber Polyacrylate-acrylic acid ester Acrylester rubber Poly (acrylic acid ester rubber)... 

In general, however, vulcanizates of straight polyacrylates are weak and do not have good ageing properties. Consequently, commercial acrylate rubbers... 

Standard-grade PSAs are usually made from styrene-butadiene rubber (SBR), natural rubber, or blends thereof in solution. In addition to rubbers, polyacrylates, polymethylacrylates, polyfvinyl ethers), polychloroprene, and polyisobutenes are often components of the system ([198], pp. 25-39). These are often modified with phenolic resins, or resins based on rosin esters, coumarones, or hydrocarbons. Phenolic resins improve temperature resistance, solvent resistance, and cohesive strength of PSA ([196], pp. 276-278). Antioxidants and tackifiers are also essential components. Sometimes the tackifier will be a lower molecular weight component of the high polymer system. The phenolic resins may be standard resoles, alkyl phenolics, or terpene-phenolic systems ([198], pp. 25-39 and 80-81). Pressure-sensitive dispersions are normally comprised of special acrylic ester copolymers with resin modifiers. The high polymer base used determines adhesive and cohesive properties of the PSA. 

HMX HMX HMX HMX HMX HMX HMX HMX HMX HMX HMX HMX HNS NTO NTO/HMX NTO/HMX NTO/HMX PETN PETN PETN PETN PETN PETN PETN PETN PETN PETN RDX RDX RDX RDX RDX RDX RDX RDX RDX RDX RDX RDX RDX TATB/HMX Cariflex (thermoplastic elastomer) Hydroxy-terminated polybutadiene (polyurethane) Hydroxy-terminated polyester Kraton (block copolymer of styrene and ethylene-butylene) Nylon (polyamide) Polyester resin-styrene Polyethylene Polyurethane Poly(vinyl) alcohol Poly(vinyl) butyral resin Teflon (polytetrafluoroethylene) Viton (fluoroelastomer) Teflon (polytetrafluoroethylene) Cariflex (block copolymer of butadiene-styrene) Cariflex (block copolymer of butadiene-styrene) Estane (polyester polyurethane copolymer) Hytemp (thermoplastic elastomer) Butyl rubber with acetyl tributylcitrate Epoxy resin-diethylenetriamine Kraton (block copolymer of styrene and ethylene-butylene) Latex with bis-(2-ethylhexyl adipate) Nylon (polyamide) Polyester and styrene copolymer Poly(ethyl acrylate) with dibutyl phthalate Silicone rubber Viton (fluoroelastomer) Teflon (polytetrafluoroethylene) Epoxy ether Exon (polychlorotrifluoroethylene/vinylidine chloride) Hydroxy-terminated polybutadiene (polyurethane) Kel-F (polychlorotrifluoroethylene) Nylon (polyamide) Nylon and aluminium Nitro-fluoroalkyl epoxides Polyacrylate and paraffin Polyamide resin Polyisobutylene/Teflon (polytetrafluoroethylene) Polyester Polystyrene Teflon (polytetrafluoroethylene) Kraton (block copolymer of styrene and ethylene-butylene)... 

For cellulose nitrate, polyacrylates of higher alcohols have proved to give very smooth and transparent films. Good results are obtained with polybutyl acrylate and polyethylhexyl acrylate. The polyacrylates of higher alcohols can be used as plasticizers for rubber. Oligomers of acrylates can not be used in combination with PVC, because they give only hard films. 

The combination of durability and clarity and the ability to tailor molecules relatively easily to specific applications have made acrylic esters prime candidates for numerous and diverse applications. At normal temperatures the polyacrylates are soft polymers and therefore tend to find use in applications that require flexibility or extensibility. However, the ease of copolymerizing the softer acrylates with the harder methacrylates, styrene, acrylonitrile, and vinyl acetate, allows the manufacture of products that range from soft rubbers to hard nonfihn-formitig polymers. 

Polyacrylate elastomers find limited use in HydrauHc systems and gasket appHcations because of their superior heat resistance compared to the nitrile rubbers (219,220). Ethylene—acrylate copolymers were introduced in 1975. The appHcations include transmission seals, vibration dampers, dust boots, and steering and suspension seals. Further details and performance comparisons with other elastomers are given in reference 221 (see also Elastomers,... 

Poly([ethyl acrylate]-g-plvalolactone) was found to be easily processable on conventional rubber working equipment. It was easily processable on a two-roll mill, had excellent calendering properties, could be compression molded at 225-230°C, and could be Injection molded at 225°C. Extrusion was more difficult requiring high temperatures (250°C) and slow extrusion rates. Physical properties of the graft copolymers were similar to those of the parent elastomeric polyacrylates that had been compounded with carbon block and chemically crossllnked. 

The polyacrylate and ethylene-acrylic copolymers and one of the ethylene-propylene terpolymers (Nordel) were the best of the Intermediate temperature elastomers. Except for resistance to compression set, these materials were Inferior to the silicones in thermal stability as measured by their retention of tensile properties. The other EPDM compounds and butyl rubber were considerably inferior to the above-mentioned elastomers. It is not expected that the service life of the tested materials will be limited solely by their ability to resist hydrolytic degradation. The only caulking compositions which retained moderate physical integrity on thermal aging were the silicones. 

The above criteria were employed to select several commercially supplied Class PS elastomers for laboratory screening by employing selected tests taken from National Bureau of Standards NBSIR 77-1437(j4) and ANSI/ASTM D-3667-78 specifications for "Rubber Seals Used in Flat-Plate Solar Collectors". Four silicone, three EPDM, two fluorocarbon, three epichlorohydrin, one ethylene-acrylic, one polyacrylic, one chlorosulfonated polyethylene, one bromobutyl and two butyl rubbers were studied in these screening tests. These materials are identified in Table I and those compositions which were revealed by their manufacturers are shown in Table II. Undoubtedly some materials which should have been included were omitted however, we hope that this sampling will provide an indication of the applicability of a wide range of materials for use as sealants in thermal solar collectors. 

Polyacrylates are produced commercially by free-radical-initiated solution and emulsion polymerization of the appropriate monomer. Unlike for methacrylates, suspension and casting procedures are not feasible because of the rubber and adhesive nature of higher acrylates. 

Acrylic aldehyde. See Acrolein Acrylic amide. See Acrylamide Acrylic copolymer. See Acrylates copolymer Acrylic elastomer Synonyms Polyacrylic rubber Uses Textile, nonwoven, adhesive bindings, coatings, finishes, seals and gaskets Features Low temp.-resistant Trade Name Synonyms Cyanacryl 35 f [Cytec Ind. http //www.cytec.com]] HyStretch T-35 t[Noveon http //www.noveoninc.com] http //WWW. carbopoi. com] http //www.noveoncoatings.com]] HyStretch V-29 [Noveon http //www.noveoninc.com] http //WWW. carbopoi. com http //www.noveoncoatings.com]] HyStretch ... 

Additol XL 480. See Acrylates copolymer Additol XW330. See Ammonium polyacrylate Adeka EP-4100. See Epoxy resin Adeka GH-200. See PPG-24-glycereth-24 Adeka PA Series. See Palmitic acid Adeka PEG-200. See PEG-4 Adeka PEG-300. See PEG-6 Adeka PEG-400. See PEG-8 Adeka PEG-600. See PEG-12 Adeka PEG-1000. See PEG-20 Adeka Chlorinated Rubber CR-5. See Rubber, chlorinated... 

Cyanoethyl acrylate textile sizing Hydroxyethylcellulose textile sizing, polyamide/polyester Polyacrylic acid textile soil-release finishes Polymethacrylic acid Sodium polyacrylate textile thread, elastomeric Natural rubber latex textile treatment... 

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